1. Field of the Invention
This invention relates to a process for producing a porous body of tourmaline that enables the tourmaline to thoroughly manifest its ionizing effect.
2. Prior Art Statement
Tourmaline has to be used in the form of a fine powder to take advantage of its ionizing effect. Finely comminuted tourmaline is, however, difficult to use "as is" in either water or air. The ordinary practice has therefore been to sinter it with a ceramic. The magnitude of the ionizing effect produced by tourmaline is proportional to the area thereof in contact with water or air. Products produced by the prior art are therefore inefficient because they can utilize only the very small percentage of the tourmaline exposed at the surface. Moreover, the sintering of the mixture of tourmaline and ceramic requires high-temperature heating. This makes production difficult because tourmaline loses its useful electrical properties when heated to a high temperature of, for example, 950 C or higher.